Journal articles: 'Fault analysis/power systems'

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Tiwari, Ravi Kumar, Nidhi Singh, Ambarish Kumar, and D. Suresh Babu. "Analysis of Symmetrical Fault with Fault Impedance in Power System." Global Journal For Research Analysis 2, no. 1 (June 15, 2012): 64–66. http://dx.doi.org/10.15373/22778160/january2013/63.

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Guo, Xiaoxiao, Yanghong Tan, and Feng Wang. "Modeling and Fault Propagation Analysis of Cyber–Physical Power System." Energies 13, no. 3 (January 22, 2020): 539. http://dx.doi.org/10.3390/en13030539.

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In cyber–physical power systems (CPPSs), the interaction mechanisms between physical systems and cyber systems are becoming more and more complicated. Their deep integration has brought new unstable factors to the system. Faults or attacks may cause a chain reaction, such as control failure, state deterioration, or even outage, which seriously threatens the safe and stable operation of power grids. In this paper, given the interaction mechanisms, we propose an interdependent model of CPPS, based on a characteristic association method. Utilizing this model, we can study the fault propagation mechanisms when faulty or under cyber-attack. Simulation results quantitatively reveal the propagation process of fault risks and the impacts on the CPPS due to the change of state quantity of the system model.

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Amanze, Fortune Chukwuebuka, and Amanze Destiny Josiah. "Fault analysis in power system using power systems computer aided design." International Journal of Advances in Applied Sciences 9, no. 3 (September 1, 2020): 171. http://dx.doi.org/10.11591/ijaas.v9.i3.pp171-179.

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<span>This work presents a fault analysis simulation model of an IEEE 30 bus system in a distribution network. This work annalysed the effect of fault current and fault voltage in a distribution system. A circuit breaker was introduced into the system to neutralize the effect of the fault. The system was run on a PSCAD software and results were obtained. The system was monitored based on the start time and the end time of the fault and how well the circuit breaker reacts with those times. Fault occurred from 0.100 to 0.300 seconds before it was removed. At the time fault was not applied (i.e. from 0.00 to 0.100 and from 0.300 to 0.72), the circuit breaker was close and became open when fault was applied so as to cut off current flow through the line.The result obtained gave the disruption caused by the fault and the quick response of the circuit breaker in neutralizing it. Results gotten are based on when the circuit breaker is close and no fault is applied and when the circuit breaker is open due to fault. From this work, it was obtained that circuit breakers are very essential in system protection and reliability.</span>

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Djibo, Marounfa `., Paul Moses, and Ike Flory. "Fault Protection Considerations for MVDC Shipboard Power Systems Operating with Pulsed-Power Loads." WSEAS TRANSACTIONS ON POWER SYSTEMS 16 (August 2, 2021): 139–48. http://dx.doi.org/10.37394/232016.2021.16.14.

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Medium Voltage Direct Current (MVDC) power distribution architectures are of immense interest for various shipboard power applications due to their advantages over classical MVAC distribution systems with respect to power quality, power density, and efficiency. However, MVDC are far away from maturity when compared to MVAC with respect to fault detection and isolation. Currently, there are no standards available for applying MVDC protection systems in shipboard applications. Furthermore, due to the absence of zero crossings in DC waveforms and unique transient fault signatures, it is challenging to design effective protection system schemes to isolate faults via conventional protection systems. This paper investigates and analyses various types of shipboard MVDC dynamic fault behaviours and signatures under different DC bus disturbances such as: bus to ground, bus to bus to ground, and impact of Pulsed-Power Load (PPL) with and without faults on a shipboard MVDC distribution system. Furthermore, a communication-based fault detection and isolation system controller that improves upon a directional ac overcurrent relay protection system is proposed offering additional protection discrimination between faults and PPLs in MVDC systems. To validate the effectiveness of the proposed protection controller, different bus current disturbances are simulated within a time-domain electromagnetic transient simulation of a shipboard power system including a PPL system operating with different ramp rate profiles, pulse widths, peak powers, and fault locations

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Gururajapathy, Sophi Shilpa, Hazlie Mokhlis, and Hazlee Azil Illias. "Fault location using mathematical analysis and database approach." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 38, no. 1 (January 7, 2019): 415–30. http://dx.doi.org/10.1108/compel-02-2018-0077.

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PurposeThe purpose of this paper is to identify faults in distribution systems which are unavoidable because of adverse weather conditions and unexpected accidents. Hence, quick fault location is vital for continuous power supply. However, most fault location methods depend on the stored database for locating fault. The database is created by simulation, which is time consuming. Therefore, in this work, a comprehensive fault location method to detect faulty section and fault distance from one-ended bus using limited simulated data is proposed.Design/methodology/approachThe work uses voltage sag data measured at a primary substation. Support vector machine estimates the data which are not simulated. The possible faulty section is determined using matching approach and fault distance using mathematical analysis.FindingsThis work proposed a ranking analysis for multiple possible faulty sections, and the fault distance is calculated using Euclidean distance approach.Practical implicationsThe research work uses Malaysian distribution system as it represents a practical distribution system with multiple branches and limited measurement at primary substation. The work requires only metering devices to identify fault which is cost effective. In addition, the distribution system is simulated using real-time PSCAD by which the capability of proposed method can be fully tested.Originality/valueThe paper presents a new method for fault analysis. It reduces simulation time and storage space of database. The work identifies faulty section and ranks the prior faulty section. It also identifies fault distance using a mathematical approach.

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Lu, Cheng, Xi Lin Zhang, Biao Long Su, and Yi Jun Wang. "Simulation of Fault Treatment Performance for Distribution Automation Systems and Key Technologies of Training Systems." Advanced Materials Research 1092-1093 (March 2015): 345–51. http://dx.doi.org/10.4028/www.scientific.net/amr.1092-1093.345.

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The simulation of fault treatment performance for distribution automation systems and the key technologies of training systems are discussed in this paper, which include key technologies for basic platform, auxiliary decision-making analysis for grid faults, load-transfer analysis for power system operating mode, loop closing analysis for power system operating mode and distribution network training simulation and so on. The results of simulation of fault treatment performance for distribution automation systems and training systems operation show a good accuracy and effectiveness of the method.

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Parzinger, Michael, Lucia Hanfstaengl, Ferdinand Sigg, Uli Spindler, Ulrich Wellisch, and Markus Wirnsberger. "Residual Analysis of Predictive Modelling Data for Automated Fault Detection in Building’s Heating, Ventilation and Air Conditioning Systems." Sustainability 12, no. 17 (August 20, 2020): 6758. http://dx.doi.org/10.3390/su12176758.

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Faults in Heating, Ventilation and Air Conditioning (HVAC) systems affect the energy efficiency of buildings. To date, there rarely exist methods to detect and diagnose faults during the operation of buildings that are both cost-effective and sufficient accurate. This study presents a method that uses artificial intelligence to automate the detection of faults in HVAC systems. The automated fault detection is based on a residual analysis of the predicted total heating power and the actual total heating power using an algorithm that aims to find an optimal decision rule for the determination of faults. The data for this study was provided by a detailed simulation of a residential case study house. A machine learning model and an ARX model predict the building operation. The model for fault detection is trained on a fault-free data set and then tested with a faulty operation. The algorithm for an optimal decision rule uses various statistical tests of residual properties such as the Sign Test, the Turning Point Test, the Box-Pierce Test and the Bartels-Rank Test. The results show that it is possible to predict faults for both known faults and unknown faults. The challenge is to find the optimal algorithm to determine the best decision rules. In the outlook of this study, further methods are presented that aim to solve this challenge.

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WANG, C., and Y. ZHANG. "Fault Correspondence Analysis in Complex Electric Power Systems." Advances in Electrical and Computer Engineering 15, no. 1 (2015): 11–16. http://dx.doi.org/10.4316/aece.2015.01002.

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Xiu, Wanjing, and Yuan Liao. "Fault-location Observability Analysis on Power Distribution Systems." Electric Power Components and Systems 42, no. 16 (November 3, 2014): 1862–71. http://dx.doi.org/10.1080/15325008.2014.956953.

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Zhu Yongli, Y. H. Yang, B. W. Hogg, W. Q. Zhang, and S. Gao. "An expert system for power systems fault analysis." IEEE Transactions on Power Systems 9, no. 1 (1994): 503–9. http://dx.doi.org/10.1109/59.317573.

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Caseiro, Luís, and André Mendes. "Fault Analysis and Non-Redundant Fault Tolerance in 3-Level Double Conversion UPS Systems Using Finite-Control-Set Model Predictive Control." Energies 14, no. 8 (April 15, 2021): 2210. http://dx.doi.org/10.3390/en14082210.

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Fault-tolerance is critical in power electronics, especially in Uninterruptible Power Supplies, given their role in protecting critical loads. Hence, it is crucial to develop fault-tolerant techniques to improve the resilience of these systems. This paper proposes a non-redundant fault-tolerant double conversion uninterruptible power supply based on 3-level converters. The proposed solution can correct open-circuit faults in all semiconductors (IGBTs and diodes) of all converters of the system (including the DC-DC converter), ensuring full-rated post-fault operation. This technique leverages the versatility of Finite-Control-Set Model Predictive Control to implement highly specific fault correction. This type of control enables a conditional exclusion of the switching states affected by each fault, allowing the converter to avoid these states when the fault compromises their output but still use them in all other conditions. Three main types of corrective actions are used: predictive controller adaptations, hardware reconfiguration, and DC bus voltage adjustment. However, highly differentiated corrective actions are taken depending on the fault type and location, maximizing post-fault performance in each case. Faults can be corrected simultaneously in all converters, as well as some combinations of multiple faults in the same converter. Experimental results are presented demonstrating the performance of the proposed solution.

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Han, Jaeyoung, Sangseok Yu, and Jinwon Yun. "PEMFC Transient Response Characteristics Analysis in Case of Temperature Sensor Failure." Processes 8, no. 11 (October 26, 2020): 1353. http://dx.doi.org/10.3390/pr8111353.

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In this study, transient responses of a polymer electrolyte fuel cell system were performed to understand the effect of sensor fault signal on the temperature sensor of the stack and the coolant inlet. We designed a system-level fuel cell model including a thermal management system, and a controller to analyze the dynamic behavior of fuel cell system applied with variable sensor fault scenarios such as stuck, offset, and scaling. Under drastic load variations, transient behavior is affected by fault signals of the sensor. Especially, the net power of the faulty system is 45.9 kW. On the other hand, the net power of the fault free system is 46.1 kW. Therefore, the net power of a faulty system is about 0.2 kW lower than that of a fault-free system. This analysis can help in understanding the transient behavior of fuel cell systems at the system level under fault situations and provide a proper failure avoidance control strategy for the fuel cell system.

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Rong, Haina, Kang Yi, Gexiang Zhang, Jianping Dong, Prithwineel Paul, and Zhiwei Huang. "Automatic Implementation of Fuzzy Reasoning Spiking Neural P Systems for Diagnosing Faults in Complex Power Systems." Complexity 2019 (June 19, 2019): 1–16. http://dx.doi.org/10.1155/2019/2635714.

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As an important variant of membrane computing models, fuzzy reasoning spiking neural P systems (FRSN P systems) were introduced to build a link between P systems and fault diagnosis applications. An FRSN P system offers an intuitive illustration based on a strictly mathematical expression, a good fault-tolerant capacity, a good description for the relationships between protective devices and faults, and an understandable diagnosis model-building process. However, the implementation of FRSN P systems is still at a manual process, which is a time-consuming and hard labor work, especially impossible to perform on large-scale complex power systems. This manual process seriously limits the use of FRSN P systems to diagnose faults in large-scale complex power systems and has always been a challenging and ongoing task for many years. In this work we develop an automatic implementation method for automatically fulfilling the hard task, named membrane computing fault diagnosis (MCFD) method. This is a very significant attempt in the development of FRSN P systems and even of the membrane computing applications. MCFD is realized by automating input and output, and diagnosis processes consists of network topology analysis, suspicious fault component analysis, construction of FRSN P systems for suspicious fault components, and fuzzy inference. Also, the feasibility of the FRSN P system is verified on the IEEE14, IEEE 39, and IEEE 118 node systems.

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Gord, Ehsan, Rahman Dashti, Mojtaba Najafi, and Hamid Reza Shaker. "Real Fault Section Estimation in Electrical Distribution Networks Based on the Fault Frequency Component Analysis." Energies 12, no. 6 (March 24, 2019): 1145. http://dx.doi.org/10.3390/en12061145.

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: Fault location in electrical energy distribution networks is an important task, as faults in distribution grids are among the main causes of electricity supply disruption. Fault location in the distribution systems, however, is a challenging task because of the topology of the distribution networks, as well as the main and side branches. Therefore, it is necessary to address these challenges through an intelligent approach to fault location. In this paper, fault location in electric energy distribution networks is addressed considering the changes in fault distance and fault resistance in the presence of different fault types. A new method for fault location is developed for conditions where the minimum information is available and only information at the beginning of the feeder is used. This facilitates wide adoption of the technique as it does not require significant investments in instrumentation and measurement. The proposed intelligent method is based on the impedance and transient state estimation. This technique employs a specific impedance analysis for determining possible fault locations considering the unbalanced performance of distribution systems, distances, and different fault resistances. To determine the real faulty section, real fault frequency component analysis and the simulated faults at possible fault locations are used. At this stage of the process, it is possible to eliminate multiple estimations with the help of comparison and identification of the similarities. Therefore, a real faulty section is determined. It is observed that some conditions of electric energy distribution networks affect the accuracy and performance of the proposed method significantly; thus, a detailed investigation is conducted to neutralize these conditions. Simulation results and calculations based on MATLAB along with a practical test of the proposed method in power network simulator confirm a satisfactory performance.

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Diamenu, Godwin. "Statistical Analysis of Electric Power Distribution Grid Outages." European Journal of Engineering and Technology Research 6, no. 3 (April 12, 2021): 27–33. http://dx.doi.org/10.24018/ejers.2021.6.3.2406.

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Power systems in general supply consumers with electrical energy as economically and reliably as possible. Reliable electric power systems serve customer loads without interruptions in supply voltage. Electric power generation facilities must produce enough power to meet customer demand. Electrical energy produced and delivered to customers through generation, transmission and distribution systems, constitutes one of the largest consumers markets the world over. The benefits of electric power systems are integrated into the much faster modern life in such extent that it is impossible to imagine the society without the electrical energy. The rapid growth of electric power distribution grids over the past few decades has resulted in a large increment in the number of grid lines in operation and their total length. These grid lines are exposed to faults as a result of lightning, short circuits, faulty equipment, mis-operation, human errors, overload, and aging among others. A fault implies any abnormal condition which causes a reduction in the basic insulation strength between phase conductors or phase conductors and earth, or any earthed screens surrounding the conductors. In this paper, different types of faults that affected the electric power distribution grid of selected operational districts of Electricity Company of Ghana (ECG) in the Western region of Ghana was analyzed and the results presented. Outages due to bad weather and load shedding contributed significantly to the unplanned outages that occurred in the medium voltage (MV) distribution grid. Blown fuse and loose contact faults were the major contributor to unplanned outages in the low voltage (LV) electric power distribution grid.

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Filomena, André D., Mariana Resener, Rodrigo H. Salim, and Arturo S. Bretas. "Distribution systems fault analysis considering fault resistance estimation." International Journal of Electrical Power & Energy Systems 33, no. 7 (September 2011): 1326–35. http://dx.doi.org/10.1016/j.ijepes.2011.06.010.

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Jamuna, Venkatesan, Natesan Saritha, and N. Nanthini. "Fault Analysis on Photo Voltaic Fed Grid Connected Systems." Advanced Materials Research 984-985 (July 2014): 1013–22. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.1013.

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This work presents a photovoltaic (PV) system, connected to a three phase grid. This work focuses on fault analysis in a grid connected photo-voltaic (PV) energy system. In this work, a three phase Multi-level Inverter connected with an AC grid fed by photovoltaic systems with advanced sine PWM control scheme is presented. The proposed modulation technique uses single reference signal and number of high frequency carrier signals to generate the PWM signal. Now a days, most of the photovoltaic (PV) power sources are connected to the AC grid. When photovoltaic power sources are connected to grid, the grid connected PV system is affected by various power quality issues like voltage sag, voltage swell, voltage disturbances, waveform distortions and three phase fault. One of the main power quality problems is three phase fault and it is appeared in the grid due to short circuit condition between two phases and ground. Fault analysis is carried out by creating a LG, LL, LLL and LLLG fault in the grid connected systems. Grid side voltage, current and power waveforms at the grid side are analysed with fault conditions. A detailed simulation has been done for the Multi-Level Inverter and the validation of system is verified through MATLAB/SIMULINK and the results are presented.

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Raza, Ali, Abdeldjabar Benrabah, Thamer Alquthami, and Muhammad Akmal. "A Review of Fault Diagnosing Methods in Power Transmission Systems." Applied Sciences 10, no. 4 (February 14, 2020): 1312. http://dx.doi.org/10.3390/app10041312.

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Transient stability is important in power systems. Disturbances like faults need to be segregated to restore transient stability. A comprehensive review of fault diagnosing methods in the power transmission system is presented in this paper. Typically, voltage and current samples are deployed for analysis. Three tasks/topics; fault detection, classification, and location are presented separately to convey a more logical and comprehensive understanding of the concepts. Feature extractions, transformations with dimensionality reduction methods are discussed. Fault classification and location techniques largely use artificial intelligence (AI) and signal processing methods. After the discussion of overall methods and concepts, advancements and future aspects are discussed. Generalized strengths and weaknesses of different AI and machine learning-based algorithms are assessed. A comparison of different fault detection, classification, and location methods is also presented considering features, inputs, complexity, system used and results. This paper may serve as a guideline for the researchers to understand different methods and techniques in this field.

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Liao, Yuan. "A Novel Fault Location Method for Radial Distribution Systems." International Journal of Emerging Electric Power Systems 16, no. 3 (June 1, 2015): 225–32. http://dx.doi.org/10.1515/ijeeps-2014-0036.

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Abstract This paper presents a new method for locating faults on radial distribution systems utilizing local voltage and current measurements. The method considers feeder shunt capacitances, is applicable to any type of faults, is suitable for unbalanced networks and does not require fault type information. The method is also independent of source impedance. Analytical analysis is utilized to obtain a generic performance equation for any type of faults, which reduces or eliminates iterative steps to reach the fault location. A process to trim down multiple estimates due to laterals is discussed. Evaluation studies based on simulated data have demonstrated the effectiveness of the proposed solution.

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Casoli, Paolo, Andrea Bedotti, Federico Campanini, and Mirko Pastori. "A Methodology Based on Cyclostationary Analysis for Fault Detection of Hydraulic Axial Piston Pumps." Energies 11, no. 7 (July 18, 2018): 1874. http://dx.doi.org/10.3390/en11071874.

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Condition monitoring has been an active area of research in many industrial fields during the last decades, particularly in fluid power systems. This paper presents a solution for the fault diagnosis of a variable displacement axial-piston pump, which is a critical component in many hydraulic systems. The proposed methodology follows a data-driven approach including data acquisition and feature extraction and is based on the analysis of acceleration signals through the theory of cyclostationarity. An experimental campaign was carried out on a laboratory test bench with the pump in the flawless state and in faulty states. Different operating conditions were considered and each test was repeated several times in order to acquire a suitable population to verify data repeatability. Results showed the capability of the proposed approach of detecting a typical fault related to worn slippers. Future works will include tests in order to apply the approach to a wider set of faults and the development of a classifier for accurate fault identification.

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Oyama, Tsutomu, and Akira Horiguchi. "Fault section estimation in power systems by discrimination analysis." Electrical Engineering in Japan 115, no. 1 (February 1995): 10–21. http://dx.doi.org/10.1002/eej.4391150102.

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Nazarov, Artyom, Vitaliy Savelev, and Dennis Frogh. "The investigation of frequency response analysis for power transformers winding condition." E3S Web of Conferences 139 (2019): 01023. http://dx.doi.org/10.1051/e3sconf/201913901023.

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In modern electrical transmission and distribution systems, power transformers are critical components within the network. In the event that a failure occurs in service, the impact can be far reaching. The majority of mechanical deformation within power transformers is due to short circuit faults. The ageing transformer population increases the likelihood of failure so a reliable diagnostic tools required to determine the remaining life of these assets. Although, frequency response analysis (FRA) has been recently recognized as the most reliable detection tool for mechanical deformation in transformers, in the event of minor fault, the current FRA interpretation approach may not able to detect any variations between healthy and faulty FRA signatures. This paper focuses on FRA tests for power transformer and interpretation of obtained FRA signatures.

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Urbaha, Margarita, Arnis Križus, and Deniss Kreisberg. "Ship Power System Analysis Based on Safety Aspects." Transport and Aerospace Engineering 4, no. 1 (August 1, 2017): 96–105. http://dx.doi.org/10.1515/tae-2017-0012.

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Abstract This article analyses the reasons for the reduction of insulating resistance, processes influencing them and isolation diagnostic methods. It provides a short description of electrical safety situation on ships with isolated neutral electrical power systems. It also covers the methods of protecting personnel from electric shock or preventing ignition or arching damage at the fault location with the help of fault current compensation. Principal fault current compensation circuit diagrams are analysed by using the minimum value and time of transient fault current as criteria.

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Mousavi, Yashar, Geraint Bevan, Ibrahim Beklan Küçükdemiral, and Afef Fekih. "Maximum Power Extraction from Wind Turbines Using a Fault-Tolerant Fractional-Order Nonsingular Terminal Sliding Mode Controller." Energies 14, no. 18 (September 17, 2021): 5887. http://dx.doi.org/10.3390/en14185887.

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This work presents a nonlinear control approach to maximise the power extraction of wind energy conversion systems (WECSs) operating below their rated wind speeds. Due to nonlinearities associated with the dynamics of WECSs, the stochastic nature of wind, and the inevitable presence of faults in practice, developing reliable fault-tolerant control strategies to guarantee maximum power production of WECSs has always been considered important. A fault-tolerant fractional-order nonsingular terminal sliding mode control (FNTSMC) strategy to maximize the captured power of wind turbines (WT) subjected to actuator faults is developed. A nonsingular terminal sliding surface is proposed to ensure fast finite-time convergence, whereas the incorporation of fractional calculus in the controller enhances the convergence speed of system states and simultaneously suppresses chattering, resulting in extracted power maximisation by precisely tracking the optimum rotor speed. Closed-loop stability is analysed and validated through the Lyapunov stability criterion. Comparative numerical simulation analysis is carried out on a two-mass WT, and superior power production performance of the proposed method over other methods is demonstrated, both in fault-free and faulty situations.

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Biscaro, A. A. P., R. A. F. Pereira, M. Kezunovic, and J. R. S. Mantovani. "Integrated Fault Location and Power-Quality Analysis in Electric Power Distribution Systems." IEEE Transactions on Power Delivery 31, no. 2 (April 2016): 428–36. http://dx.doi.org/10.1109/tpwrd.2015.2464098.

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Hou, Xin Guo, Jia Lin Wang, Guo Bin Du, and Le Ping Bu. "Heuristic Topology Analysis of the Shipboard Power Systems Based on Petri Net Modify." Advanced Materials Research 732-733 (August 2013): 1010–15. http://dx.doi.org/10.4028/www.scientific.net/amr.732-733.1010.

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According to the characteristic of the shipboard power system, heuristic search for fast tracking shipboard power system network topology is introduced. Using for reference of the methods of fault diagnosis of the power systems, the Petri net technology is used to fault location and removal of uncertain and fault signals, which can modify the topology analysis results. Setting the topology analysis and remodel based on Petri net of the typical shipboard power system for example, the results is validated.

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Austin, Oshin Ola, Oluwasanmi Alonge, and Ajayi Joseph Adeniyi. "Fault Diagnosis Algorithm and Protection of Electric Power Systems in an Alternative Distribution System." Journal La Multiapp 1, no. 3 (December 1, 2020): 8–16. http://dx.doi.org/10.37899/journallamultiapp.v1i3.192.

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In any power systems, protective devices will detect fault conditions and operate circuit breakers in order to disconnect the load from the fault current and limit loss of service due to failure. This fault may involve one or more phases and the ground, or may occur between two or more phases in a three-phase systems. In ground, fault’ or ‘earth fault, current flows into the earth. In a poly-phase system, a fault may affect each of the three phases equally which is a symmetrical fault. If only some phases are affected, the resulting ‘asymmetrical fault’ becomes more complicated to analyze due to the simplifying assumption of equal current magnitude in all the phases being no longer applicable. Therefore, the prospective short circuit current of the fault can be calculated for power systems analysis procedures. This will assist in the choice of protective devices like circuit breakers, current transformers and relays. This research work evaluated and analyzed the occurrence of faults in a distribution system. Fault currents were obtained and the maximum tripping time required for the protective devices to operate were determined. Hence, it was possible to select appropriate relay and circuit breaker for effective operation of a distribution

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Tuyou, Si, Wu Jiekang, Yuan Weideng, and Du Anan. "Power supply risk assessment method for relay protection system faults." Archives of Electrical Engineering 65, no. 4 (December 1, 2016): 803–14. http://dx.doi.org/10.1515/aee-2016-0056.

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Abstract The influence and the potential risk due to hidden faults of a relay protection system on power supply in distribution systems are paid more and more attention to. A probability analysis method is used to analyse fault characteristics and action mechanism of dominant faults, hidden misoperation and non-operation of the relay protection systems, and failure probability model of relay protection system is constructed and simplified. The effects of dominant faults, hidden misoperation and non-operation of the relay protection systems on the reduced power supply load power are analysed, and a probabilistic model for reduced power supply load power is constructed by three parts corresponding to dominant faults, hidden misoperation and non-operation. A probability calculation method of power supply risk occurrence due to hidden faults of relay protecttion system is proposed considering the fault probability of the relay protection systems, the frequency of the hidden faults occurring in operation period, the reduced power supply load power or load power outage, and the connection mode of the in-lines, out-lines and transformers in a substation. The feasibility and applicability of the proposed method for estimation of risk value probability of the relay protection systems is verified by two studied examples.

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Deliparaschos, Kyriakos, Konstantinos Michail, and Argyrios Zolotas. "Facilitating Autonomous Systems with AI-Based Fault Tolerance and Computational Resource Economy." Electronics 9, no. 5 (May 11, 2020): 788. http://dx.doi.org/10.3390/electronics9050788.

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Proposed is the facilitation of fault-tolerant capability in autonomous systems with particular consideration of low computational complexity and system interface devices (sensor/actuator) performance. Traditionally model-based fault-tolerant/detection units for multiple sensor faults in automation require a bank of estimators, normally Kalman-based ones. An AI-based control framework enabling low computational power fault tolerance is presented. Contrary to the bank-of-estimators approach, the proposed framework exhibits a single unit for multiple actuator/sensor fault detection. The efficacy of the proposed scheme is shown via rigorous analysis for several sensor fault scenarios for an electro-magnetic suspension testbed.

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Halpin, S. M., and L. L. Grigsby. "Fault analysis of multi-phase unbalanced nonradial power distribution systems." IEEE Transactions on Industry Applications 31, no. 3 (1995): 528–34. http://dx.doi.org/10.1109/28.382113.

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Mustarum Musaruddin, and Rastko Zivanovic. "Web Services for Automated Fault Analysis in Electrical Power Systems." INTERNATIONAL JOURNAL ON Advances in Information Sciences and Service Sciences 2, no. 3 (September 30, 2010): 76–81. http://dx.doi.org/10.4156/aiss.vol2.issue3.10.

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Baek, Sejin, and Gyunyoung Heo. "Application of Dynamic Fault Tree Analysis to Prioritize Electric Power Systems in Nuclear Power Plants." Energies 14, no. 14 (July 8, 2021): 4119. http://dx.doi.org/10.3390/en14144119.

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Because the scope of risk assessments at nuclear power plants (NPPs) is being extended both spatially and temporally, conventional, or static fault trees might not be able to express failure mechanisms, or they could be unnecessarily conservative in their expression. Therefore, realistic assessment techniques are needed to adequately capture accident scenarios. In multi-unit probabilistic safety assessment (PSA), fault trees naturally become more complex as the number of units increases. In particular, when considering a shared facility between units of the electric power system (EPS), static fault trees (SFTs) that prioritize a specific unit are limited in implementing interactions between units. However, dynamic fault trees (DFTs) can be available without this limitation by using dynamic gates. Therefore, this study implements SFTs and DFTs for an EPS of two virtual NPPs and compares their results. In addition, to demonstrate the dynamic characteristics of the shared facilities, a station blackout (SBO), which causes the power system to lose its function, is assumed—especially with an inter-unit shared facility, AAC DG (Alternate AC Diesel Generator). To properly model the dynamic characteristics of the shared EPS in DFTs, a modified dynamic gate and algorithm are introduced, and a Monte Carlo simulation is adopted to quantify the DFT models. Through the analysis of the DFT, it is possible to confirm the actual connection priority of AAC DG according to the situation of units in a site. In addition, it is confirmed that some conservative results presented by the SFT can be evaluated from a more realistic perspective by reflecting this.

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Zhang, Yichi, Tao Shu, Xincheng Song, Yan Xu, and Pengxiang Zhang. "Research on Fault Diagnosis of Launch Vehicle’s Power Transformation and Transmission System Based on Big Data." Mathematical Problems in Engineering 2021 (July 21, 2021): 1–11. http://dx.doi.org/10.1155/2021/3108000.

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The on-board power supply system provides power for the launch vehicle. The power transmission and transformation system plays an irreplaceable role to ensure that the on-board power supply system receives the normal working voltage of the launch vehicle. There are many types of faults in power transmission and transformation systems. The traditional faulty diagnosis method of power transmission and transformation equipment has the disadvantages of being susceptible to experts’ subjectivity and model’s ossification. In this paper, a new method of equipment fault diagnosis based on big data is proposed. On the basis of big data, this paper introduces the failure mode clustering algorithm, the state parameter correlation analysis algorithm, the fault diagnosis method based on the correlation matrix, and other key fault diagnosis technologies. The fault record data of the 400 kV voltage grade oil-immersed transformer bushing in the past ten years by a Chinese combat unit is used as a case for demonstration. The results show that the accuracy rate of SC-LSTM-K-means clustering model exceeds 95%. And the fault classification mode can be accurately obtained. A priori correlation algorithm with TA coefficient can be used to evaluate the strong and weak relationship between the state parameters; the fault diagnosis matrix based on Pearson’s correlation coefficient can accurately determine the fault mode consistent with the actual operation and maintenance test results. Therefore, the fault diagnosis method of power transmission and transformation system based on big data can both effectively obtain the inherent laws of historical data and realize more accurate fault diagnosis with data adaptability.

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Bayati, Navid, and Mehdi Savaghebi. "Protection Systems for DC Shipboard Microgrids." Energies 14, no. 17 (August 27, 2021): 5319. http://dx.doi.org/10.3390/en14175319.

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In recent years, shipboard microgrids (MGs) have become more flexible, efficient, and reliable. The next generations of future shipboards are required to be equipped with more focuses on energy storage systems to provide all-electric shipboards. Therefore, the shipboards must be very reliable to ensure the operation of all parts of the system. A reliable shipboard MG should be protected from system faults through protection selectivity to minimize the impact of faults and facilitate detection and location of faulty zones with the highest accuracy and speed. It is necessary to have an across-the-board overview of the protection systems in DC shipboards. This paper provides a comprehensive review of the issues and challenges faced in the protection of shipboard MGs. Furthermore, given the different types of components utilized in shipboard MGs, the fault behavior analysis of these components is provided to highlight the requirements for their protection. The protection system of DC shipboards is divided into three sub-systems, namely, fault detection, location, and isolation. Therefore, a comprehensive comparison of different existing fault detection, location, and isolation schemes, from traditional to modern techniques, on shipboard MGs is presented to highlight the advantages and disadvantages of each scheme.

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Chaudhary, Rekha, and Arun Kumar Singh. "Analysis and design of different controllers for non-linear power systems." International Journal of Engineering & Technology 2, no. 3 (July 25, 2013): 216. http://dx.doi.org/10.14419/ijet.v2i3.1050.

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The objective of this paper is to design controller for non-linear power system using Direct Feedback Linearization technique to improve the transient stability and to achieve better voltage regulation. In case of fault in the power system, power angle and the terminal voltage are the parameters which are to be monitored. The simulation has been carried out taking different values of initial power angles and results were obtained for power angle and terminal voltage. To overcome the demerits of DFL-LQ optimal controller and DFL voltage regulator, co-ordinated controller is proposed. Simulation results show that transient stability of a power system under a large sudden fault has been improved by using co-ordinated controller.

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Zhang, Jun. "Recognition of the Single-Phase Ground Fault in Power Distribution System." Key Engineering Materials 480-481 (June 2011): 1581–86. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.1581.

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For power distribution systems, recognizing the single-phase ground fault is very difficult because there are several faults with similar features. This paper presents a novel method that can help to overcome this difficulty. The idea is to turns the original fault info into a whole system with transient state, steady state and transition state. Theoretical analysis, computer simulation and lab experiments verified the effectiveness of the proposed method.

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Shang, Haikun, Junyan Xu, Zitao Zheng, Bing Qi, and Liwei Zhang. "A Novel Fault Diagnosis Method for Power Transformer Based on Dissolved Gas Analysis Using Hypersphere Multiclass Support Vector Machine and Improved D–S Evidence Theory." Energies 12, no. 20 (October 22, 2019): 4017. http://dx.doi.org/10.3390/en12204017.

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Power transformers are important equipment in power systems and their reliability directly concerns the safety of power networks. Dissolved gas analysis (DGA) has shown great potential for detecting the incipient fault of oil-filled power transformers. In order to solve the misdiagnosis problems of traditional fault diagnosis approaches, a novel fault diagnosis method based on hypersphere multiclass support vector machine (HMSVM) and Dempster–Shafer (D–S) Evidence Theory (DET) is proposed. Firstly, proper gas dissolved in oil is selected as the fault characteristic of power transformers. Secondly, HMSVM is employed to diagnose transformer fault with selected characteristics. Then, particle swarm optimization (PSO) is utilized for parameter optimization. Finally, DET is introduced to fuse three different fault diagnosis methods together, including HMSVM, hybrid immune algorithm (HIA), and kernel extreme learning machine (KELM). To avoid the high conflict between different evidences, in this paper, a weight coefficient is introduced for the correction of fusion results. Results indicate that the fault diagnosis based on HMSVM has the highest probability to identify transformer faults among three artificial intelligent approaches. In addition, the improved D–S evidence theory (IDET) combines the advantages of each diagnosis method and promotes fault diagnosis accuracy.

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Alsafasfeh, Qais H., Ikhlas Abdel-Qader, and Ahmad M. Harb. "Fault Classification and Localization in Power Systems Using Fault Signatures and Principal Components Analysis." Energy and Power Engineering 04, no. 06 (2012): 506–22. http://dx.doi.org/10.4236/epe.2012.46064.

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Morales, John, Eduardo Muñoz, Eduardo Orduña, and Gina Idarraga-Ospina. "A Novel Approach to Arcing Faults Characterization Using Multivariable Analysis and Support Vector Machine." Energies 12, no. 11 (June 3, 2019): 2126. http://dx.doi.org/10.3390/en12112126.

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Based on the Institute of Electrical and Electronics Engineers (IEEE) Standard C37.104-2012 Power Systems Relaying Committee report, topics related to auto-reclosing in transmission lines have been considered as an imperative benefit for electric power systems. An important issue in reclosing, when performed correctly, is identifying the fault type, i.e., permanent or temporary, which keeps the faulted transmission line in service as long as possible. In this paper, a multivariable analysis was used to classify signals as permanent and temporary faults. Thus, by using a simple convolution process among the mother functions called eigenvectors and the fault signals from a single end, a dimensionality reduction was determined. In this manner, the feature classifier based on the support vector machine was used for acceptably classifying fault types. The algorithm was tested in different fault scenarios that considered several distances along the transmission line and representation of first and second arcs simulated in the alternative transients program ATP software. Therefore, the main contribution of the analysis performed in this paper is to propose a novel algorithm to discriminate permanent and temporary faults based on the behavior of the faulted phase voltage after single-phase opening of the circuit breakers. Several simulations let the authors conclude that the proposed algorithm is effective and reliable.

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Sabbaghpur Arani, M., and M. A. Hejazi. "The Comprehensive Study of Electrical Faults in PV Arrays." Journal of Electrical and Computer Engineering 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/8712960.

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The rapid growth of the solar industry over the past several years has expanded the significance of photovoltaic (PV) systems. Fault analysis in solar photovoltaic (PV) arrays is a fundamental task to increase reliability, efficiency, and safety in PV systems and, if not detected, may not only reduce power generation and accelerated system aging but also threaten the availability of the whole system. Due to the current-limiting nature and nonlinear output characteristics of PV arrays, faults in PV arrays may not be detected. In this paper, all possible faults that happen in the PV system have been classified and six common faults (shading condition, open-circuit fault, degradation fault, line-to-line fault, bypass diode fault, and bridging fault) have been implemented in 7.5 KW PV farm. Based on the simulation results, both normal operational curves and fault curves have been compared.

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Stemmle, M., C. Neumann, F. Merschel, U. Schwing, K. H. Weck, M. Noe, F. Breuer, and S. Elschner. "Analysis of Unsymmetrical Faults in High Voltage Power Systems With Superconducting Fault Current Limiters." IEEE Transactions on Applied Superconductivity 17, no. 2 (June 2007): 2347–50. http://dx.doi.org/10.1109/tasc.2007.899136.

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Kim, Tae-Wook, Jaewon Oh, Cheonhong Min, Se-Yun Hwang, Min-Seok Kim, and Jang-Hyun Lee. "An Experimental Study on Condition Diagnosis for Thrust Bearings in Oscillating Water Column Type Wave Power Systems." Sensors 21, no. 2 (January 11, 2021): 457. http://dx.doi.org/10.3390/s21020457.

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In order to utilize wave energy, various wave power systems are being actively researched and developed and interest in them is increasing. To maximize the operational efficiency, it is very important to monitor and maintain the fault of components of the system. In recent years, interest in the management cost, high reliability and facility utilization of such systems has increased. In this regard, fault diagnosis technology including fault factor analysis and fault reproduction is drawing attention as an important main technology. Therefore, in this study, to reproduce and monitor the faults of a wave power system, firstly, the failure mode of the system was analyzed using FMEA analysis. Secondly, according to the derived failure mode and effect, the thrust bearing was selected as a target for fault reproduction and a test equipment bench was constructed. Finally, with the vibration data obtained by conducting the tests, the vibration spectrum was analyzed to extract the features of the data for each operating status; the data was classified by applying the three machine learning algorithms: naïve Bayes (NB), k-nearest neighbor (k-NN), and multi-layer perceptron (MLP). The criteria for determining the fault were derived. It is estimated that a more efficient fault diagnosis is possible by using the standard and fault monitoring method of this study.

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Kim, Tae-Wook, Jaewon Oh, Cheonhong Min, Se-Yun Hwang, Min-Seok Kim, and Jang-Hyun Lee. "An Experimental Study on Condition Diagnosis for Thrust Bearings in Oscillating Water Column Type Wave Power Systems." Sensors 21, no. 2 (January 11, 2021): 457. http://dx.doi.org/10.3390/s21020457.

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In order to utilize wave energy, various wave power systems are being actively researched and developed and interest in them is increasing. To maximize the operational efficiency, it is very important to monitor and maintain the fault of components of the system. In recent years, interest in the management cost, high reliability and facility utilization of such systems has increased. In this regard, fault diagnosis technology including fault factor analysis and fault reproduction is drawing attention as an important main technology. Therefore, in this study, to reproduce and monitor the faults of a wave power system, firstly, the failure mode of the system was analyzed using FMEA analysis. Secondly, according to the derived failure mode and effect, the thrust bearing was selected as a target for fault reproduction and a test equipment bench was constructed. Finally, with the vibration data obtained by conducting the tests, the vibration spectrum was analyzed to extract the features of the data for each operating status; the data was classified by applying the three machine learning algorithms: naïve Bayes (NB), k-nearest neighbor (k-NN), and multi-layer perceptron (MLP). The criteria for determining the fault were derived. It is estimated that a more efficient fault diagnosis is possible by using the standard and fault monitoring method of this study.

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Zeng, Xiao Hui, Yong Hui Chen, and Gong Quan Tan. "A Fault Phase Selection Method Based on Arc Voltages for High-Voltage Line Protections in Electric Power Systems." Advanced Materials Research 676 (March 2013): 218–21. http://dx.doi.org/10.4028/www.scientific.net/amr.676.218.

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A fault phase selection method is proposed based on arc voltage after analysis of inadequate of fault phase selector existed in the paper. A precise fault phase selection can be achieved by using arc voltages in conjunction with phase current differences and sequence components of currents. The method proposed can solve false tripping problems in transmission line protections when single phase to ground faults occur with great reliabilities. Simulation results show that the method can identify faulted phase or phases correctly and effectively.

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Ivanchenko, Daniil, and Artem Smirnov. "Identification of interturn faults in power transformers by means of generalized symmetrical components analysis." E3S Web of Conferences 140 (2019): 04007. http://dx.doi.org/10.1051/e3sconf/201914004007.

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The paper deals with experimental identification of transformer internal faults, an important factor in reliability and sustainability of power supply systems. Task of identification of transformer internal faults requires increasing sensitivity of relay protection by calculation of components most sensitive to interwire faults from transformer current. In order to study internal faults in transformer, the model in Simulink MATLAB was developed on the basis of transformer constitutive equations. Transformer with short circuited wires was simulated as a multiwinding transformer. We provide the calculation of transformer parameters. Model was applied for analysis of transients in power transformers, such as interwire fault, transformer inrush, and fault in transformer connections. Analysis of power transformer internal faults by means of time-dependent symmetrical components of currents is provided. These symmetrical components were calculated for the first harmonic of current by means of discrimination of firs harmonic by low-pass filter and compensating elements implementing phase shift. Described method allows calculation of symmetrical components during transient and under non-sinusoidal conditions. Simulation results showed the advantage of instantaneous symmetrical components of other direct values. Those components were implemented in relay protection algorithms for identification of internal faults in transformers.

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Aphrodis, Nduwamungu, Ntagwirumugara Etienne, Utetiwabo Wellars, and Mulolani Francis. "Dynamic grid fault analysis in wind power plant with DFIG by using supervisory control and data acquisition (SCADA) viewer." E3S Web of Conferences 181 (2020): 03006. http://dx.doi.org/10.1051/e3sconf/202018103006.

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Faults in electrical power systems are among the key factors and sources to network disturbances, however control strategies are among key faults clearing techniques for the sake of safe operational mode of the system.Some researchers have shown various limitations of control strategies such as slow dynamic response,inability to switch Off and On network remotely and fault clearing time. For a system with wind energy technologies, if the power flow of a wind turbine is interrupted by a fault, the intermediate-circuit voltage between the machine-side converter and line-side converter will fall in unacceptably high values.To overcome the aforementioned issues, this paper used a Matlab simulations and experiments in order to analyze and validate the results.The results showed that fault ride through (FRT) with SCADA Viewer software are more adaptable to the variations of voltage and wind speed in order to avoid loss of synchronism. Therefore at the speed of 12.5m/s a wind produced a rated power of 750W and remained in synchronization before and after a fault created and cleared but worked as generator meanwhile at speed of 3.4m/s wind disconnected from grid and started working as a motor and consumed active power (P=-25watts) and voltage dip at 100% .For the protection purpose, the DC chopper and crowbar should be integrated towards management of excess energy during faults cases.

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Salomon, Camila Paes, Claudio Ferreira, Wilson Cesar Sant’Ana, Germano Lambert-Torres, Luiz Eduardo Borges da Silva, Erik Leandro Bonaldi, Levy Ely de Lacerda de Oliveira, and Bruno Silva Torres. "A Study of Fault Diagnosis Based on Electrical Signature Analysis for Synchronous Generators Predictive Maintenance in Bulk Electric Systems." Energies 12, no. 8 (April 21, 2019): 1506. http://dx.doi.org/10.3390/en12081506.

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The condition of synchronous generators (SGs) is a matter of great attention, because they can be seen as equipment and also as fundamental elements of power systems. Thus, there is a growing interest in new technologies to improve SG protection and maintenance schemes. In this context, electrical signature analysis (ESA) is a non-invasive technique that has been increasingly applied to the predictive maintenance of rotating electrical machines. However, in general, the works applying ESA to SGs are focused on isolated machines. Thus, this paper presents a study on the condition monitoring of SGs in bulk electric systems by using ESA. The main contribution of this work is the practical results of ESA for fault detection in in-service SGs interconnected to a power system. Two types of faults were detected in an SG at a Brazilian hydroelectric power plant by using ESA, including stator electrical unbalance and mechanical misalignment. This paper also addresses peculiarities in the ESA of wound rotor SGs, including recommendations for signal analysis, how to discriminate rotor faults on fault patterns, and the particularities of two-pole SGs.

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Kalyani, V. Mohana, J. Preetha Roselyn, C. Nithya, and D. Devaraj. "Enhanced Crowbar Protection for Fault Ride through Capability of Wind Generation Systems." International Journal of Power Electronics and Drive Systems (IJPEDS) 7, no. 4 (December 1, 2016): 1366. http://dx.doi.org/10.11591/ijpeds.v7.i4.pp1366-1376.

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Due to increasing demand in power, the integration of renewable sources like wind generation into power system is gaining much importance nowadays. The heavy penetration of wind power into the power system leads to many integration issues mainly due to the intermittent nature of the wind and the desirability for variable speed operation of the generators. As the wind power generation depends on the wind speed, its integration into the grid has noticeable influence on the system stability and becomes an important issue especially when a fault occurs on the grid. The protective disconnection of a large amount of wind power during a fault will be an unacceptable consequence and threatens the power system stability. With the increasing use of wind turbines employing Doubly Fed Induction Generator (DFIG) technology, it becomes a necessity to investigate their behavior during grid faults and support them with fault ride through capability. This paper presents the modeling and simulation of a doubly fed induction generator according to grid code compatibility driven by a wind turbine connected to the grid. This paper analyses the voltage sag due to a three-phase fault in the wind connected grid. A control strategy including a crowbar circuit has been developed in MATLAB/SIMULINK to bypass the rotor over currents during grid fault to enhance the fault ride through capability and to maintain system stability. Simulation results show the effectiveness of the proposed control strategies in DFIG based grid connected wind turbine system.

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Guan, Yong, Sheng Zhen Jin, Li Feng Wu, Wei Pan, Yong Mei Liu, and Jie Zhang. "Power Supply Prognostics and Health Management of High Reliability Electronic Systems in Rugged Environment." Key Engineering Materials 474-476 (April 2011): 1195–200. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.1195.

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The high reliable embedded system in rugged environment has huge potential application value. There are 34% faults in electronic system by the cause of the fault of power system. So the prognostics mechanism and the algorithm of power health has been a core support technology in applications. the fault and the deterioration and healing model of the power system in rugged environment is constructed by analysis of FFP, DFP and healing(alleviation)for improving the reliability, the usability and the maintainability. And many questions such as fixed-time maintenance and back-down maintenance depending on conventional statistical method are solved fundamentally. Finally, the prognostics and health management methods of power health in domestic and foreign presently are contrasted and analyzed.

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Chao, Kuei-Hsiang, and Chen-Hou Ke. "Fault Diagnosis and Tolerant Control of Three-Level Neutral-Point Clamped Inverters in Motor Drives." Energies 13, no. 23 (November 29, 2020): 6302. http://dx.doi.org/10.3390/en13236302.

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This paper presents an extension theory-based assessment method to perform fault diagnosis for inverters in motor driving systems. First, a three-level neutral-point clamped (NPC) inverter is created using the PSIM software package to simulate faults for any power transistor in the NPC-type inverter. Fast Fourier transformation is used to transform the line current signals in the time domain into a spectrum in the frequency domain for analysis of the corresponding spectrum of features of the inverter for faults with different power transistors. Then, the relationships between fault types and specific spectra are established as characteristics for the extension assessment method, which is then used to create a smart fault diagnosis system for inverters. Fault-tolerant control (FTC) is used here when the rated output of a faulty inverter is decreased in order to maintain balanced output in three phases by changing the framework of the transistor connection. This is performed to reinforce the reliability of the inverter. Finally, by the simulation and experimental results, the feasibility of the proposed smart fault diagnosis system is confirmed. The proposed fault diagnosis method is advantageous due to its minimal use of data and lack of a learning process, which thereby reduces the fault diagnosis time and makes the method easily used in practice. The proposed fault-tolerant control strategy allows both online and smooth switching in the wiring structure of the inverter.

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Journal articles on the topic 'Fault analysis/power systems'

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